Have the Progressive EMS unit..... IMHO, one of the best out there....

Does more than just surge protection; analyzes the incoming shore power for under/over voltage, open neutral (extremely important) and other items before energizing the coach. Takes about 10-15 seconds when you first plugin to actually energize the coach.

FWIW, I do not have the Hughes device. I've never plugged in where the Progressive unit indicated a low voltage; so I don't see that the Autoformer would help me at all.

Progressive Industries for me. Once we moved to another site because of an open neutral, twice the power to the RV was cut off because of surges in line voltage. Mine is paid for.
Travel safe

Yes, and for those who might be "electrically challenged" an open neutral brings 240V right into your coach and burns up EVERYTHING. The Progressive unit will even cut power before any damage can happen, should the neutral become open AFTER you've been plugged in for awhile.

Other units may be just as sophisticated, but I don't if any are. You will pay around $350 for this level of protection, though.

A lot of folks don't know this, but 50A service is actually 100A service if using only 120 volts. 50A's come in on each of the two "hots" giving 100A for both sides of the circuit. So, it's been explained to me anyway.....

Thanks all. BooHoo, I think both are imperative with these coaches. Seems to me we NEED the surge protection but we also NEED the voltage regulation of the Autoformers. If voltage drops due to hot days, ie. the park fluctuating as people plug in and unplug.... The A/C's, microwave, fridge, computers, etc... can burn out. There's some overlap between the devices; but, with both everything is covered! Cheap insurance even with warranties as your time in repair shop is worth something!

Thanks all. BooHoo, I think both are imperative with these coaches. Seems to me we NEED the surge protection but we also NEED the voltage regulation of the Autoformers. If voltage drops due to hot days, ie. the park fluctuating as people plug in and unplug.... The A/C's, microwave, fridge, computers, etc... can burn out. There's some overlap between the devices; but, with both everything is covered! Cheap insurance even with warranties as your time in repair shop is worth something!

That is the point I was trying to make.... My EMS will shut down INSTANTLY in the case of over voltage, under voltage and a host of other potentially damaging conditions.

Will anything be able to operate while whatever condition exists? NO. Will it with the Autoformer? I don't know. But I've NEVER had my EMS shut down for an extended length of time.

In fact, now that I think about it, I've NEVER plugged in at any park, where after the 15 second "diagnostic" mode, the relay didn't snap closed and energize the whole coach.

The EMS can even be optioned so it was not cycle in/out rapidly as some fridge's and other items can be damaged that way. I think I've got mine set to shut down for AT LEAST 15 seconds, no matter how short the problem "event" may be.

There is a small readout in the convenience panel that lists (via error code) the nature if any problem that occurs.

I could have used a booster a couple of times in 175 campgrounds due to low voltage. Had to unplug the EMS to get power to the trailer and didn't run the A/C. Herk is the only member here that I know of that uses an autoformer.

I am confused. What is the difference between the transfer switch on our Berks and a surge protector.

After reading documentation on transfer switch is look as though it does an analysis of power before putting it thru to the house. How does this differ from a built in surge protector as discussed above.

We have a power monitor system in our coach. When we got with the engineers at Coachmen, they told us it will asses and monitor, but will not shut down the input to the coach. This was a year ago, I would guess the systems in the Berkshire are similar. It's my understanding all a transfer switch does is transfer power from gen set to shore power and vice versa.

I've had the Progressive EMS for several years and it tells me if there is a line problem BEFORE I plug in.
Just replaced my Auto Transfer Switch [$310] with a mechanical transfer switch [$40 with 50 amp breaker]. Got tired of fooling around with the "auto" switch which has never worked right.
No all I have to do is remember which way it is set before turning on the inverter or shore power. I hung a red flag on the inverter switch to help me remember. I'm getting old and memory sucks!
Anyway, never heard anyone having trouble with the EMS unit. Sorry about the rambling.

I am confused. What is the difference between the transfer switch on our Berks and a surge protector.

After reading documentation on transfer switch is look as though it does an analysis of power before putting it thru to the house. How does this differ from a built in surge protector as discussed above.

Are both devices required?

I was unaware that the transfer switch was that sophisticated. Maybe they are on newer coaches (mine is 2011). I don't think mine is that "smart".

But if yours is that intelligent then maybe you don't need an EMS unit.

Again, the EMS continually "watches" for any abnormality and shuts the power down instantly before any damage can be done. Kinda like a GFI device.

Agree with Boowho. The transfer switch does not analyze voltage or current amount. It is a traffic cop and determines which AC power the cabin gets, depending upon whether the generator is running or plugged into shore power.

Another vote for the Progressive EMS. Ours has saved us from low voltage several times, a couple of open grounds, and a missing neutral. It is also a surge protector, but you don't know when its MOVs absorb a surge as their is no indication. I suspect it absorbs surges fairly regularly. The Progressive EMS is by far the best product of its kind available.